The movie Interstellar involves many interesting scientific concepts, including the fluidity of time. On Earth, time moves at the same speed for all of us – otherwise our watches would constantly need to change how fast they move. However, time can change in two specific scenarios.

If someone is moving significantly faster than us on Earth

If someone is under the effects of more gravity than us on Earth

Astronauts on the International Space Station (ISS) experience this. As they orbit the Earth, the gravitational pull keeps them in orbit, and makes them move much faster than we are on Earth. As a result, they age less than us.

If the same astronauts wanted to head away from Earth at an extremely fast speed – near the speed of light – they would age slower than us during the trip. If the destination was an object with more significantly more gravity than the Earth – like a black hole – they would continue to age slower while under the effects of increased gravity.

That’s the genius of media – you can enjoy the adventure and emotion presented in the movie, and OPTIONALLY it can spark a light of curiosity that leads one to further research.